READ MORE: Carol Vorderman works out with Alex Scott in incredible video but one fan notices something unusualThey added: "To the egg donor that we have never met or seen any pic of THANK YOU without you our bundle of joy would not be here.
And @effidy_dowling_ you have given us THE WORLD we will forever owe YOU. Merci. " The baby was born on Thursday afternoon and weighed 7lb 4ozs.
The announcement of the baby comes as the pair are set to have a TV series released which follows their journey into parenthood.
It will also follow Brian's sister, Aoife, on her journey as a surrogate. The show will air on RTE and is called A Very Modern Irish Family – Brian and Arthur’s Surrogacy Story.
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